  import React, { Component } from 'react'

  export default class App extends Component {
    state = {
      isLiked: true
    }
    render() {
      const { isLiked } = this.state
      let str = ''
      // 不推荐
      if (isLiked) {
        str = <div style={{ fontSize: 100 }}>😍</div>
      } else {
        str = <div style={{ fontSize: 100 }}>💔</div>
      }
      return (
        <>
          <h1>标题</h1>
          { str }
        </>
      )
    }
  }
